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conquest by Genghis Khan

It is probable that Turks were incorporated in the nascent Mongol empire. In a series of tribal wars that led to the defeat of the
Merkits and the Naimans, his most dangerous rivals, Genghis gained sufficient strength to assume, in 1206, the title of khan. Acting in the tradition of previous nomad empires of the region, Genghis directed his aggressive policies primarily against China, then...

...as members of the royal Borjigin clan, in spite of their rejection by it. Among other things, he was able to claim the wife to whom Yesügei had betrothed him just before his death. But the
Merkit people, a tribe living in northern Mongolia, bore Temüjin a grudge, because Yesügei had stolen his own wife, Höelün, from one of their men, and in their turn they ravished...